Conventional carpet tile has historically been a product that sought to mimic the appearance of broadloom carpet and to hide or at least de-emphasize the fact that the product was modular. Achieving this result has required, at minimum, that carpet tiles or modules be placed in a flooring installation with the same orientation, and often in the same relative position on the web, that the modules had at the time they were produced. This is because conventional carpet tiles, particularly including tufted, fusion bonded, or woven face carpet tiles, normally have a “direction” as a result of (1) the manufacturing process and/or (2) the pattern on the tiles.
Conventional production techniques, particularly including tufting techniques, cause the carpet pile to lean or have a nap direction. This property of conventional carpet modules causes a tile (even a solid color tile) within a field of tiles to have a different appearance, particularly under certain lighting and viewing conditions, if it is oriented in a different direction than the tiles with which it is placed. Thus, historically the tiles have all been oriented in the same direction (i.e., they all have uniform rotational orientation). Uniform rotational orientation during module installation is facilitated by the presence of direction indicia on the modules, which usually is placed on the back or underside of the modules, and requires careful attention to rotational orientation during installation. In addition to concerns about nap direction, minor variations in color require that carpet tiles in a particular installation all use yarn dyed in the same dye lot to avoid visually discernable differences between adjacent carpet tiles resulting from variations in dying.
Moreover, the presence of a pattern that spans more than one tile in the web from which the tiles are cut has also sometimes required that not only the rotational orientation of tiles in an installation be the same but for the tiles to be located in particular relative positions. Thus, after the carpet web is cut into tiles, the tiles must be oriented on the floor so that their pattern aligns with the patterns on adjacent tiles or with the appearance of adjacent tiles. Indeed, schemes for insuring or facilitating placement of modular carpet in predetermined relative positions (as well as rotational orientation) have been developed. One such approach is suggested in U.S. Pat. Nos. 6,197,400 and 6,203,879, both to Desai.
Most carpet tiles are square. If a first carpet tile is placed on the floor, a second tile may be placed in four different positions relative to each side of the first tile by rotating the second tile in 90° increments relative to the first carpet tile and may be placed in four different locations by placing the second tile adjacent to each of the four sides of the first tile. In only one of the second tile's four rotational positions is the second tile oriented in the same “direction” as the first tile, so that both tiles are in the same rotational orientation as they were relative to each other in the carpet web from which they were cut or as they came off of the carpet producing machine. Moreover, some patterns used on carpet tiles require that the second tile be placed only adjacent to a particular side or sides of the first tile, rather than adjacent to any of the four sides of the first tile. If one carpet tile in an installation is oriented improperly with respect to adjacent carpet tiles, it is usually readily apparent that the tile has been misplaced, thereby destroying the appearance of continuity of pattern, nap, and color of the entire carpet tile installation. The carpet installer, therefore, must spend valuable time during installation ensuring proper orientation of the tiles. Moreover, an important benefit of modular flooring is the opportunity it affords to easily replace selected portions of the flooring, such as when a carpet tile is stained or worn. Often, however, a replacement carpet tile will be unacceptably prominent in appearance when installed together with tiles that have been in use for some time.
One approach to some of the challenges associated with modular flooring described above has been to produce first a web, and then modules of flooring, that are uniform in color and carry no pattern, so that only nap direction and dye lot are important and there are no problems of registration between a tile pattern or design and the tile edges. This makes relative tile position irrelevant. In other instances, tile producers have sought to address the design-to-module registration issues by first producing a uniform color tile or module and then printing a design on the face of the tile that is positioned by reference to the tile edges after the tile is cut from the web. There are, however, design, cost and functional limitations associated with printing on textile face modular flooring. A third approach has been to use relatively small design elements so that such elements at a tile edge will not look odd near tile edges or if they are cut by tile edges.
Moreover, textile face modular flooring designers have recently begun to design flooring and flooring installations that do not seek to mask, but rather showcase or celebrate, the modularity of the flooring. For instance, modules are installed “quarter-turned” with each tile position rotated 90° relative to each adjacent tile. In other instances, module edges are emphasized to achieve an installation appearance similar to that of ceramic tile separated by grout.
There continues, however, to be substantial demand for flooring designs that do not visually emphasize the modularity of flooring components but instead appear to have a design that spans the entire flooring installation or part of the flooring installation rather than appearing to be confined to individual modules so that the modules may be placed in any orientation with respect to adjacent carpet tiles while still achieving the appearance of broadloom carpet.